Field of Invention
The present invention relates to a reflective display device.
Description of Related Art
In the current market of various consumer electronic products, portable electronic devices have extensively utilized reflective display devices, such as the electronic paper display device, as display screens. An electronic ink (e-ink) layer of a reflective display device is mainly made of an electrophoresis buffer and white and black charged particles that are doped in the electrophoresis buffer. The white and black charged particles are driven to move by applying a voltage to the e-ink layer, so as to present individual pixel with black, white or a gray level. The reflective display device utilizes an incident light that irradiates the e-ink layer and is reflected to human eyes by the e-ink layer to achieve the purpose of display.
In general, reflected lights of the reflective display device entering human eyes include light that is reflected by the e-ink layer and light that is reflected by other material layers. When the proportion of the light reflected by other material layers except e-ink layer is high, the proportion of the incident light entering the e-ink layer is low. As a result, the reflected light of the e-ink layer is apt to be interfered by the light that is reflected by other material layers. When the reflected light of the e-ink layer along with other reflected light enters a human's eyes, the image quality, the contrast, and the color saturation of the reflective display device are reduced, thereby affecting visual perception.
In a typical reflective display device, optical clear adhesive is often used to adhere an additional anti-reflective layer. However, the thickness of the anti-reflective layer and the thickness of the optical clear adhesive is substantial. Therefore, the light transmittance of the reflective display device is reduced, and the manufacturing cost of the reflective display device is typically increased. For example, the thickness of the anti-reflective layer is usually greater than 100 μm. Moreover, when the reflective display device has a light guide plate of a front light module, a glass having a color filter is usually adhered to an electrophoretic display module, such that the glass with the color filter is under the light guide plate. As a result, it is difficult to reduce the thickness of the entire reflective display device, and light entering the e-ink layer is decreased due to the increased layers of the reflective display device.